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PubMed1995

Sodium nitroprusside does not influence tissue oxygen extraction capabilities during a critical reduction in oxygen delivery.

By its regulating effects on blood vessel tone, nitric oxide (NO) may play an important role in the coupling of oxygen delivery (DO2) to metabolic rate. We reasoned that if endogenous NO synthesis is an important modulator of oxygen extraction ratio (O2ER), then administration of a NO donor will alter oxygen extraction capabilities during a fall in blood flow. We studied the effects of the NO donor, nitroprusside, on the relationship between DO2 and oxygen uptake (VO2) during an acute reduction in DO2 induced by cardiac tamponade. Twenty-one healthy, anaesthetised, mechanically ventilated dogs were randomly divided into 3 groups. Group 1 (n = 7) served as control; Groups 2 and 3 were given sodium nitroprusside at 1.0 microgram/kg.min (n = 7), and 2.5 micrograms/kg.min intravenously (n = 7), respectively. All animals were given normal saline i.v. at a rate of 20 ml/kg.h throughout the study. Cardiac tamponade was induced by bolus injections of normal saline into the pericardial space. In the control animals the critical DO2 (DO2crit) was found at 10.1 +/- 1.5 ml/kg.min and critical O2ER (O2ERcrit) at 63.3 +/- 10.9%. Nitroprusside at the lower dose decreased systemic vascular resistance but did not significantly influence arterial pressure, cardiac output, DO2 or VO2; neither DO2crit nor O2ERcrit was altered (9.3 +/- 2.9 ml/kg.min and 70.4 +/- 20.9%). Nitroprusside at the higher dose induced significant decreases in mean arterial pressure and systemic vascular resistance, but had no significant effect on cardiac output. DO2crit (9.2 +/- 2.0 ml/kg.min) and O2ERcrit (59.8 +/- 13.2%) were similar to the control group.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

Use of a scanning densitometer or an ELISA plate reader for measurement of nanogram amounts of protein in crude extracts from biological tissues.

Protein contents of crude extracts from plant and animal tissues can be rapidly assayed using a Coomassie blue dye-binding procedure combined with scanning densitometry. Total protein is extracted from 100 mg of fresh-frozen or dried-ground tissue using 1 ml of extraction buffer. One-microliter aliquots of standard solutions or crude extracts are spotted in rows on a suitably sized sheet of Whatman 3MM chromatography paper. The dried samples are stained with Coomassie brilliant blue R-250 (0.2%, w/v, in acidified 50% MeOH) for 20 min and rinsed twice with acidified 20% MeOH. After drying, protein concentrations are read as reflectance using a scanning densitometer and peak heights or peak areas recorded using a digital integrator. In an alternative procedure, each spot is cut from the sample sheet and the dye-protein complex eluted in 1% sodium dodecyl sulfate (SDS) using an ultrasonic cleaner. Absorbance is subsequently read in a microwell sample holder at 590 nm with an enzyme-linked immunosorbent assay plate reader. Both procedures offer distinct advantages over previously reported methods. They are significantly faster when large numbers of samples are processed, they avoid interference by chlorophyll, dithiothreitol, SDS, 2-mercaptoethanol, Nonidet P-40, and phenylmethylsulfonyl fluoride (and other protease inhibitors) and they yield marked improvements in sensitivity, providing measurements of protein concentration below 100 and 200 ng.microliter-1, respectively.

Animals↗
PubMed1979

[The effect of Solcoseryl on explant cultures of the hippocampus].

Explants of hippocampus from fetal rats were cultivated in Maximow chambers in semisynthetic medium up to 12 days in vitro. The cultures were fixed Bouin, slided 15 micron, coloured with Klüver-Barrera and some morphological parameters were tested. 1. The nerve fiber index increased by influence of 1% Solcoseryl in relation to control cultures, which growed in minimal medium. An essential stimulation was observed by application of placentar serum and embryonal extract into the culture medium. 2. Die decrease of the number of neurons and glial cells per unit of area and a small decrease of the area of neuron nuclei was discussed in relation to the effect of the pharmacon Solcoseryl on O2- consumption. 3. Solcoseryl (firm Solco AG, Base) is an extract of calf blood. It can not substitute other tissue extracts.

Actihaemyl↗
PubMed1990

Stimulation and inhibition of cardiac myocyte proliferation in vitro.

We have examined the effect of crude cardiac tissue extracts as well as that of several growth factors and triiodothyronin (T3) on DNA synthesis of cardiac myocytes in culture. Extracts from embryonic and adult cardiac tissue stimulated DNA synthesis of myocytes. Atrial myocytes exhibited overall higher degree of stimulation than their ventricular counterparts and extracts from adult atrial tissue had the highest apparent mitogenic activity for atrial myocytes. We have shown that adult heart contains basic fibroblast growth factor (bFGF), especially in the atria. Transforming growth factor beta (TGF beta) and insulin-like growth factors (IGFs) are also accumulated in cardiac tissues. We found that bFGF and the IGFs stimulate myocyte cell proliferation and DNA synthesis. These factors also stimulate cardiac non-muscle proliferation, especially in the presence of serum. TGF beta inhibited proliferation and DNA synthesis and cancelled the effect of bFGF or IGFs on the myocytes. T3 also diminished the bFGF-induced mitogenic stimulation of cardiomyocytes. Our data suggest that these factors may be involved in the regulation of cardiomyocyte proliferation in vivo.

Animals↗
PubMed1976

Measurement and partial characterization of immunoreactive glucagon in gastrointestinal tissues of dogs.

We have reported previously that increasing amounts of immunoreactive glucagon (IRG), measured by four specific antisera, appeared in plasma of depancreatized insulin-deficient dogs. It was therefore concluded that pancreatectomy was not accompanied by glucagon deficiency in the dog, but instead excessive amounts of extrapancreatic IRG could contribute to the diabetic syndrome. In order to locate the source of extrapancreatic glucagon, tissue extracts were assayed with anti-glucagon sera 30-K and K-44, which cross-react minimally with crude gut extracts. IRG was detected in all gastrointestinal tissues and in the salivary glands, but not in extracts of liver, kidney, brain, heart atrium, and adenohypophysis. Immunologic dilution curves of extracts from all gastrointestinal tissues were parallel to those of the pure pancreatic glucagon standard, and both antisera (30-K and K-44) measured the same concentrations. The highest concentration of gastrointestinal IRG was found in the fundus and corpus of the stomach. Presence of IRG in gastrointestinal tissues of depancreatized dogs indicates that gastrointestinal cells can not only secrete but also store large amounts of IRG. Extracts of mucosa of stomach fundus were further purified by gel filtration on Biogel P-30 columns. The immunoreactivity in the eluate was assayed by 30-K and a strongly crossreacting antibody, K-4023. One pooled fraction corresponding to marker pancreatic glucagon in its elution volume was found to contain the largest amount of IRG and the highest specific immunoreactivity (IRG/protein concentration). This fraction showed also the highest activity in a glucagon-receptor assay system. Disc gel electrophoresis in the presence of urea resolved this fraction into three immunoreactive components, one of which was identical to pancreatic glucagon in its electrophoretic mobility. It appears, therefore, that mucosa of the upper stomach in the dog contains a polypeptide similar to pancreatic glucagon. We conclude that (a) hyperglucagonemia in the dog can result from excessive secretion of IRG not only by the pancreatic alpha cells but also by cells of the gastrointestinal tract; (b) the highest IRG concentration was found in fundus and corpus of the stomach and lower concentrations throughout the gastrointestinal tract; (c) the IRG component in the stomach displayed immunologic and physical properties similar to pancreatic glucagon.

Animals↗
PubMed2003

The chemotactic behavior of eosinophils in patients with chronic rhinosinusitis.

OBJECTIVE: To characterize peripheral eosinophil migration in patients with chronic rhinosinusitis in the presence of nasal mucin and nasal tissue extracts. STUDY DESIGN: Prospective, controlled, ex-vivo. METHODS: Peripheral blood eosinophils, nasal mucin, and nasal tissue were harvested at the time of sinus surgery in 10 patients, as well as obtained in 10 healthy control subjects. Extracts were prepared from nasal mucin and nasal tissue. A modified Boyden chamber was used to study eosinophil migration from both patients and healthy control subjects in the presence of both extracts. RESULTS: Patients with chronic rhinosinusitis and all healthy control subjects demonstrated a concentration-dependent increased migration of eosinophils in the presence of both nasal mucin and nasal tissue extracts. The percentage of migration was consistently higher for eosinophils from patients with chronic rhinosinusitis compared with control subjects. The difference attained statistical significance in the presence of 50% tissue extract (median percentage of migration, 23.3% vs. 7.8% [ P=.033]). CONCLUSIONS: Nasal mucin and nasal tissue in chronic rhinosinusitis contains chemoattractants, which can induce active eosinophil migration. The eosinophil migration from patients with chronic rhinosinusitis was consistently higher compared with eosinophils from healthy control subjects. Because the eosinophils were obtained from the peripheral blood, this finding suggests activation of eosinophils in the systemic circulation in chronic rhinosinusitis.

Chemokine CCL11↗
PubMed2006

Evaluation of 31P high-resolution magic angle spinning of intact tissue samples.

The first detailed evaluation is presented of high-resolution (31)P MRS using magic angle spinning (MAS) of intact tissue samples and comparison with the conventional method of studying tissue extracts. The main motivation is that MAS leaves the sample intact at the end of the study for histopathological evaluation. While MAS of tissue samples has previously been demonstrated for (1)H MRS, (31)P MRS is better suited to study of the phospholipid metabolites of importance in cancer. Samples of rhabdomyosarcoma and RIF-1 experimental tumours were maintained at 4 degrees C, spun at 3 kHz and measured in 28-min acquisitions at 11.7 and 14 T. Metabolite stability was evaluated using four sequential 28-min acquisitions. High-resolution MRS was performed on extracts of the same tissue samples. (31)P HR-MAS yielded well-resolved high-resolution spectra, showing peaks from phosphoethanolamine (PE), phosphocholine (PC), inorganic phosphate, glycerophosphoethanolamine and glycerophosphocholine, with linewidths in the range 3-20 Hz. In tumour samples there was no significant change in peak areas over a 2-h period, while peaks sensitive to pH (inorganic phosphate, PE and PC) showed a small change in chemical shift, corresponding to a change of 0.13 +/- 0.06 pH units. Tissue metabolite concentrations showed good agreement with concentrations measured from extracts of the same pieces of tissue. For calculation of metabolite concentrations, the measurement of a reference compound in a separate measurement is more robust than using the signal from a reference compound in the rotor with the sample. Compared with performing tissue extracts, use of MAS of intact tissue samples requires less preparation, is quicker and permits the same sample to be used for subsequent histopathology. The methodology has particular application in studying phospholipid metabolism in cancer and in monitoring tumour response to treatment, where concentrations of phospholipid-related metabolites are found to alter following response to a wide range of anti-cancer therapies.

Animals↗
PubMed2003

Human kallikrein 13: production and purification of recombinant protein and monoclonal and polyclonal antibodies, and development of a sensitive and specific immunofluorometric assay.

BACKGROUND: The aims of this study were to develop immunologic reagents and a sensitive and specific immunoassay for human kallikrein 13 (hK13) and to examine the presence of hK13 in human tissues and biological fluids. METHODS: Recombinant hK13 protein was produced and purified with use of a Pichia pastoris yeast expression system. The protein was used as an immunogen to generate mouse monoclonal and rabbit polyclonal anti-hK13 antibodies. A sandwich-type immunoassay was developed with these antibodies. The assay was used to measure hK13 in various biological fluids and tissue extracts. Immunohistochemical analysis was also performed on nondiseased and cancerous prostatic sections. RESULTS: The hK13 immunoassay had a detection limit of 0.05 micro g/L and showed no cross-reactivity with homologous kallikreins. The assay was linear at 0-20 micro g/L, and within-and between-run CVs were <10% (n = 12). hK13 was detected in tissues, including esophagus, tonsil, trachea, lung, cervix, and prostate. hK13 was also found in seminal plasma, amniotic fluid, follicular fluid, ascites of ovarian cancer patients, breast milk, and cytosolic extracts of ovarian cancer tissues. hK13 was immunohistochemically localized in epithelial cells of both nondiseased and cancerous prostate. hK13 appears to be overexpressed in 50% of ovarian cancer tissues compared with healthy ovarian tissues. Recovery of active enzyme added to milk or amniotic fluid was 70-98%, but was <20% when added to serum, suggesting rapid sequestration by protease inhibitors. In fluids and tissue extracts, hK13 was found in its free (approximately 30 kDa) form. CONCLUSIONS: This immunofluorometric assay for hK13 may be used to examine the value of hK13 as a disease biomarker and to further explore the physiologic and pathobiologic role of this enzyme in human disease.

Animals↗
PubMed1978

RNA sequences complementary to citrus exocortis viroid in nucleic acid preparations from infected Gynura aurantiaca.

Molecular hybridization with (125)I-labeled citrus exocortis viroid RNA has been used to survey nucleic acid preparations from Gynura aurantiaca for viroid complementary molecules. A differential hybridization effect was detected between nucleic acid extracts from healthy and infected tissue in which significant RNase-resistant (125)I-labeled citrus exocortis viroid resulted in hybridization studies with the infected tissue extracts. Subsequent characterization indicated that RNA from infected tissue was involved in the formation of a duplex molecule with citrus exocortis viroid RNA and had properties of an RNA.RNA hybrid. Subcellular fractionation of infected tissue indicates that the complementary RNA is present in nuclear and soluble RNA fractions. This RNA may represent an intermediate molecule in the replication of the viroid or a pathogenic expression and may have a regulatory role in the host cell.

Journal Article↗
PubMed1983

Isolation and characterization of a mutant liver aldolase in adult hereditary fructose intolerance. Identification of the enzyme variant by radioassay in tissue biopsy specimens.

Hereditary fructose intolerance (HFI) is a metabolic disorder caused by enzymic deficiency of aldolase B, a genetically distinct cytosolic isoenzyme expressed exclusively in liver, kidney, and intestine. The molecular basis of this enzyme defect has been investigated in three affected individuals from a nonconsanguineous kindred, in whom fructose-l-phosphate aldolase activities in liver or intestinal biopsy samples were reduced to 2-6% of mean control values. To identify a putative enzyme mutant in tissue extracts, aldolase B was purified from human liver by affinity chromatography and monospecific antibodies were prepared from antiserum raised in sheep. Immunodiffusion gels showed a single precipitin line common to pure enzyme and extracts of normal liver and intestine, but no reaction with extracts of brain, muscle, or HFI liver. However, weak positive staining for aldolase in hepatocyte and enterocyte cytosol was demonstrated by indirect immunofluorescence of HFI tissues. This was abolished by pretreatment with pure enzyme protein. Accordingly, a specific radioimmunoassay (detection limit 7.5 ng) was established to quantify immunoreactive aldolase B in human biopsy specimens. Extracts of tissue from affected patients gave 10-25% immunoreactive enzyme in control samples; immunoreactive aldolase in intestinal extracts from four heterozygotes was reduced (to 55%) when compared with seven samples from normal control subjects (P < 0.05). In extracts of HFI tissues, there was a sevenfold reduction in apparent absolute specific activity (1.02 vs. 8.82 U/mg) of immunoreactive fructose-l-phosphate aldolase B, but the apparent specific activity in heterozygotes (7.71 U/mg) was only slightly impaired. Displacement radioimmunotitration of aldolase B in liver supernatants showed a significant (P < 0.005) decrease in antibody avidity for immunoreactive protein in HFI tissue when compared with the pure enzyme or extract of normal control liver. Immunoaffinity chromatography on antialdolase B-Sepharose facilitated isolation and purification of enzyme from liver biopsy specimens. Active aldolase in normal liver, with substrate activity ratios and Michaelis constants identical to biochemically purified human enzyme, could be recovered from antibody columns. Chromatography on monospecific Fab' antialdolase B enabled pure enzyme protein to be retrieved quantitatively from normal control and HFI liver: direct chemical assay showed 1.88 and 1.15 mg aldolase protein/g of tissue, respectively. This confirmed that the catalytic properties of the HFI aldolase were profoundly impaired with specific activities of fructose-l-phosphate cleavage of 7.21 and 0.07 U/mg, respectively. Radioimmunoassay gave estimates of 7.66 and 1.18 U/mg, respectively. Sodium dodecyl sulfate-polyacrylamide electrophoresis indicated that immunopurified aldolase from HFI liver possessed a single subunit size similar to material from control liver extracts: M(r) 39,100 vs. 37,900+/-700 (SD) D, respectively. Electrofocusing under denaturing conditions of aldolase isolated in parallel from control and HFI liver revealed the same complement of subunits and, despite qualitative differences in distribution of bands during degradation, no additional charged species. Fructose phosphate aldolase deficiency in hereditary fructose intolerance is attended by the synthesis of an immunoreactive, but functionally and structurally modified enzyme variant that results from a restricted genetic mutation.

Adolescent↗
PubMed1979

Determination by radioimmunoassay of the sum of oxidized and reduced forms of NAD and NADP in picomole quantities from the same acid extract.

The sum of the amounts of NAD + NADH was determined from the same acid tissue extract with the aid of a highly specific radioimmunoassay for 5'-AMP. NAD was converted to 5'-AMP via ADP-ribose by alkaline treatment while NADH was converted first to ADP-ribose by incubation of the acid extract at 25 degrees C followed by alkaline conversion to 5'-AMP. Removal of phosphate groups in NADP and NADPH by treatment of the extracts with alkaline phosphatase extended the procedure to the quantification of NADP(H). When combined with enzymic analyses of the oxidized coenzyme forms, NAD/NADH and NADP/NADPH ratios could also be obtained from the same extracts. The sensitivity of the test allows quantification of pyridine nucleotides in the range of 0.1--10 pmol.

Adenosine Monophosphate↗
PubMed2002

Nitric oxide induces gelatinase A (matrix metalloproteinase 2) during rat embryo implantation.

OBJECTIVE: To evaluate a reciprocal signaling interaction initiated by embryo-derived nitric oxide (NO) to facilitate implantation by increased production of gelatinase A (matrix metalloproteinase 2, MMP2) in uterine stroma. DESIGN: Experimental animal studies. SETTING: Reproductive-physiology research laboratory. ANIMAL(S): Female syngeneic Wistar rats aged 14 weeks. INTERVENTION(S): Vaginal smears to confirm pregnancy. Oviductal ligature to avoid the descent of blastocysts to the uterine lumen. Plasma exudation assays to locate uterine blastocyst implantation sites. Organ cultures treated with NO donors and nitric oxide synthase (NOS) inhibitors. MAIN OUTCOME MEASURE(S): Expression of MMP2 and NO was assessed by Western blot and zymography of tissue extracts and by immunofluorescence of tissue sections. RESULT(S): An increase in MMP2 activity was found in uterine extracts in early pregnant rats and was concentrated at implantation sites. Immunolocalization experiments showed that inducible NOS was expressed on the surface of the implanting blastocyst adjacent to the uterine epithelium at the sites of increased MMP2 expression. In organ culture experiments, NO donors were found to increase, whereas NOS inhibitors were found to decrease MMP2 activity in uterine tissue sections. CONCLUSION(S): Blastocyst-derived NO contributes to the production of uterine-derived MMP2, an essential component of implantation and initiation of placentation.

Animals↗